SOLUTION: brand x has 4 oz. and cost 1.40 brand y has 6 oz. and cost 2.16 which brand is the beter buy?

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Question 190185: brand x has 4 oz. and cost 1.40
brand y has 6 oz. and cost 2.16
which brand is the beter buy?
Found 2 solutions by jojo14344, solver91311:
Answer by jojo14344(1513) About Me  (Show Source):
You can put this solution on YOUR website!


There are certain ways to know which is better.

Brand x = 4 oz/$1.40 ; Brand y = 6 oz/$2.16

In Brand x, divide both numerator and denominator by 4 to get a price for 1 oz:
%28cross%284%29oz%2A1%2Fcross%284%29%29%2F%28cross%281.40%290.35%2Fcross%284%29%29
1 oz/$0.35

In Brand y divide both num. and den. by 6 to get a price for 1 oz:
%28cross%286%29oz%2A1%2Fcross%286%29%29%2F%28cross%282.16%290.36%2Fcross%286%29%29
1 oz/$0.36


You can see Brand x is better. You can hardly see the difference for smaller amount, buy try to fill 1 gallon tank.

We know 1 gal = 128oz

Brand x needs: 128%2F4=32oz to fill 1 gal tank, and cost you, 1.40%2A32=$44.80

Brand y needs: 128%2F6=21.33333oz to fill 1 gal tank, and cost you, 2.16%2A21.33333=$46.08


It clearly shows, the choice is Brand x to fill 1 gal tank.


Thank you,
Jojo



Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!



Divide each of the costs by the associated number of ounces, giving you the cost per ounce of each brand. Everything else being equal, the lower cost per ounce is the better buy.



John